1. Field of the Invention
The present invention relates in general to operating devices for operating automotive doors, and more particularly to operating devices of a type which opens and closes an automotive pivotal door.
2. Description of the Related art
In order to clarify the task of the present invention, some known operating devices for automotive pivotal doors will be briefly described before commencing the detailed explanation of the present invention.
Japanese Utility Model First Provisional Publication 6-71852 shows an operating device for a pivotal back door of a motor vehicle. The operating device generally comprises an electric motor which is mounted on a body of the vehicle, a pinion which is driven by the motor, a sector gear which is meshed with the pinion and pivotally held by the vehicle body and a rod member which has one end pivotally connected to the sector gear and the other pivotally connected to the pivotal back door. Upon operation of the electric motor, the pinion pivots the sector gear in one or the other direction thereby to push or pull the pivotal back door through the rod member. With this, the pivotal back door is swung toward an open or close position. For the pivotal movement of the rod member relative to both the sector gear and the pivotal back door, there are employed ball-joints respectively.
Japanese Patent First Provisional Publication 9-125820 shows a so-called semi-automatic operating device for an automotive door. That is, when, due to manual handling by an operator, the door is moved slightly toward an open or close position, the operating device senses the movement and then moves the door in the desired direction by force of an electric motor. The publication further shows a technique that avoids or lessens a shock which would be sensed by the operator when the door operation switches from the manual handling to the auto-driving. More specifically, by the technique, only when the moving speed of the door in the manual driving is within a predetermined range, the auto-driving follows. Thus, when the movement of the door by the manual handling is excessively high in speed at the beginning of door operation, the auto-driving for the door does not take place. That is, in this case, opening or closing of the door is entirely carried out by manual labor.
However, due to their inherent constructions, even the above-mentioned known operating devices have failed to provide users with a satisfaction. That is, in the former device, usage of the ball-joints brings about a complicated and costly construction, and in the latter device, even if the movement of the door by the manual handling is adequately slow, the auto-driving for the door suddenly takes place when the manual movement is kept for over a certain time, which produces a certain shock sensed by the operator.
It is therefore an object of the present invention to provide an operating device for an automotive door, which is free of the above-mentioned drawbacks.
According to a first aspect of the present invention, there is provided an operating device for operating a pivotal door, which comprises an electric motor of reversible type; a speed reduction device driven by the motor, the speed reduction device having an output part formed into an output gear; a rack member having a toothed side edge meshed with the output gear, so that upon energization of the motor, the rack member is moved axially; a motion transmitting member having one end pivotally connected to one end of the rack member and the other end connected to the pivotal door; and a structure which permits a swing movement of the rack member about an axis of the output gear when an external force is applied to the rack member in a direction to swing the same during the axial movement of the rack member.
According to a second aspect of the present invention, there is provided an operating device for use in a motor vehicle having a pivotal door which is pivotally connected at its upper end to a rear end of a roof of the vehicle. The operating device operates the pivotal door and comprises an electric motor of reversible type mounted on the rear end portion of the roof; a speed reduction device connected to and driven by the motor, the speed reduction device having an output part formed into an output gear; a rack member having a toothed side edge meshed with the output gear, so that upon energization of the motor, the rack member is moved axially; a motion transmitting member having one end pivotally connected to one end of the rack member and the other end connected to the pivotal door; a holding member for holding the rack member permitting the axial movement of the rack member relative thereto, the holding member being held by the speed reduction device in a manner to be pivotal about the axis of the output gear; two rollers rotatably connected to the holding member, each roller putting thereon the other side edge of the rack member; a cover member connected to the holding member to define therebetween a space through which the rack member axially moves; an outer slider of plastics disposed between the rack member and the cover member to smooth the axial movement of the rack member relative to the cover member; an inner slider of plastics disposed between the rack member and the holding member to smooth the axial movement of the rack member relative to the holding member; and a biasing member held by the holding member to bias the rack member toward the output gear to assure the meshed engagement between the rack member and the output gear.
According to a third aspect of the present invention, there is provided an operating device for use in a motor vehicle having a pivotal door which is pivotally connected at its upper end to a rear end of a roof of the vehicle. The operating device operates the pivotal door and comprises an electric motor of reversible type mounted on the rear end portion of the roof; a speed reduction device connected to and driven by the motor, the speed reduction device having an output part formed into an output gear; a rack member having a toothed side edge meshed with the output gear, so that upon energization of the motor, the rack member is moved axially; a motion transmitting member having one end pivotally connected to one end of the rack member and the other end connected to the pivotal door; a single roller rotatably connected to a case of the speed reduction device to put thereon the other side edge of the rack member, the roller being arranged to permit a pivotal movement of the rack member about the axis of the output gear; a cover member connected to the case of the speed reduction device to define therebetween a space through which the rack member axially moves; an outer slider of plastics disposed between the rack member and the cover member to smooth the axial movement of the rack member relative to the cover member; an inner slider of plastics disposed between the rack member and the case of the speed reduction device to smooth the axial movement of the rack member relative to the case; and a biasing member held by the case of the speed reduction device to bias the rack member toward the output gear to assure the meshed engagement between the rack member and the output gear.